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Applications of Solid-Phase Microextraction and Related Techniques

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A special issue of Molecules (ISSN 1420-3049). This special issue belongs to the section "Analytical Chemistry".

Deadline for manuscript submissions: closed (31 August 2024) | Viewed by 16853

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Prof. Dr. Hiroyuki Kataoka

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School of Pharmacy, Shujitsu University, 1-6-1, Nishigawara, Okayama 703-8516, Japan
Interests: solid-phase microextraction; chromatography; advanced glycation end products; stress hormone; biomarker; heterocyclic amines; polycyclic aromatic hydrocarbons; LC–MS/MS analysis
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Dear Colleagues,

Although a variety of high-performance analytical instruments have been developed in recent years, most of these instruments have difficulty directly handling complex matrices, such as biological, environmental, and food samples, making sample preparation essential. Among various analytical processes, from sampling to data analysis, sample preparation is the most important step in the extraction, isolation, and concentration of desired analytes in these complex matrices, and greatly influences the acquisition of reliable and accurate analysis. Thus, the development of efficient sample preparation techniques and their integration in various analytical instruments have become significant challenges.

Solid-phase microextraction (SPME) is a simple and convenient sample preparation technique that has enabled automation, miniaturization, high-throughput performance, and online coupling with analytical instruments. Moreover, SPME has reduced analysis times, as well as the costs of solvents and their disposal. Since SPME was first introduced in the early 1990s by Arthur and Pawliszyn, more robust fiber assemblies and coatings with higher extraction efficiencies, selectivity, and stability have been commercialized. Furthermore, new geometries have been designed that use capillary tubes, magnetic stir-bars, or thin films for extraction devices rather than fibers, and novel intelligent polymer coatings with great sorption capacity or good selectivity have been developed as extraction phases.

This Special Issue will include a wide range of topics, covering not only the development of SPME and related techniques, such as in-tube SPME (IT-SPME), stir-bar sorptive extraction (SBSE), thin-film microextraction (TFME), solid-phase dynamic extraction (SPDE), microextraction in a packed syringe (MEPS), and in-tip SPME, and their applications for bioanalysis, environmental, and food analyses, but also the design of new microextraction devices and novel intelligent coating materials. The aim is to present a selection of cutting-edge topics regarding sample preparation and its application in a variety of sample analyses, with the hope of fostering novel ideas and technologies.

Prof. Dr. Hiroyuki Kataoka
Guest Editor

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Keywords

solid-phase microextraction
micriextraction techniques
extraction sorbents
pharmaceutical analysis
forensic analysis
bioanalysis
environmental analysis
food analysis

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16 pages, 2415 KiB

Open AccessArticle

Vacuum-Assisted MonoTrap^TM Extraction for Volatile Organic Compounds (VOCs) Profiling from Hot Mix Asphalt

by Stefano Dugheri, Giovanni Cappelli, Niccolò Fanfani, Donato Squillaci, Ilaria Rapi, Lorenzo Venturini, Chiara Vita, Riccardo Gori, Piero Sirini, Domenico Cipriano, Mieczyslaw Sajewicz and Nicola Mucci

Molecules 2024, 29(20), 4943; https://doi.org/10.3390/molecules29204943 - 18 Oct 2024

Viewed by 495

Abstract

MonoTrap^TM was introduced in 2009 as a novel miniaturized configuration for sorptive sampling. The method for the characterization of volatile organic compound (VOC) emission profiles from hot mix asphalt (HMA) consisted of a two-step procedure: the analytes, initially adsorbed into the coating in no vacuum- or vacuum-assistance mode, were then analyzed following an automated thermal desorption (TD) step. We took advantage of the theoretical formulation to reach some conclusions on the relationship between the physical characteristics of the monolithic material and uptake rates. A total of 35 odor-active volatile compounds, determined by gas chromatography-mass spectrometry/olfactometry analysis, contributed as key odor compounds for HMA, consisting mainly of aldehydes, alcohols, and ketones. Chemometric analysis revealed that MonoTrap^TM RGC18-TD was the better coating in terms of peak area and equilibrium time. A comparison of performance showed that Vac/no-Vac ratios increased, about an order of magnitude, as the boiling point of target analytes increased. The innovative hybrid adsorbent of silica and graphite carbon monolith technology, having a large surface area bonded with octadecylsilane, showed effective adsorption capability, especially to polar compounds. Full article

(This article belongs to the Special Issue Applications of Solid-Phase Microextraction and Related Techniques)

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19 pages, 2672 KiB

Open AccessArticle

Simultaneous Determination of Tobacco Smoke Exposure and Stress Biomarkers in Saliva Using In-Tube SPME and LC-MS/MS for the Analysis of the Association between Passive Smoking and Stress

by Hiroyuki Kataoka, Saori Miyata and Kentaro Ehara

Molecules 2024, 29(17), 4157; https://doi.org/10.3390/molecules29174157 - 2 Sep 2024

Viewed by 1078

Abstract

Passive smoking from environmental tobacco smoke not only increases the risk of lung cancer and cardiovascular disease but may also be a stressor triggering neuropsychiatric and other disorders. To prevent these diseases, understanding the relationship between passive smoking and stress is vital. In this study, we developed a simple and sensitive method to simultaneously measure nicotine (Nic) and cotinine (Cot) as tobacco smoke exposure biomarkers, and cortisol (CRT), serotonin (5-HT), melatonin (MEL), dopamine (DA), and oxytocin (OXT) as stress-related biomarkers. These were extracted and concentrated from saliva by in-tube solid-phase microextraction (IT-SPME) using a Supel-Q PLOT capillary as the extraction device, then separated and detected within 6 min by liquid chromatography–tandem mass spectrometry (LC−MS/MS) using a Kinetex Biphenyl column (Phenomenex Inc., Torrance, CA, USA). Limits of detection (S/N = 3) for Nic, Cot, CRT, 5-HT, MEL, DA, and OXT were 0.22, 0.12, 0.78, 0.39, 0.45, 1.4, and 3.7 pg mL⁻¹, respectively, with linearity of calibration curves in the range of 0.01–25 ng mL⁻¹ using stable isotope-labeled internal standards. Intra- and inter-day reproducibilities were under 7.9% and 14.6% (n = 5) relative standard deviations, and compound recoveries in spiked saliva samples ranged from 82.1 to 106.6%. In thirty nonsmokers, Nic contents positively correlated with CRT contents (R² = 0.5264, n = 30), while no significant correlation was found with other biomarkers. The standard deviation of intervals between normal beats as the standard measure of heart rate variability analysis negatively correlated with CRT contents (R² = 0.5041, n = 30). After passive smoke exposure, Nic levels transiently increased, Cot and CRT levels rose over time, and 5-HT, DA, and OXT levels decreased. These results indicate tobacco smoke exposure acts as a stressor in nonsmokers. Full article

(This article belongs to the Special Issue Applications of Solid-Phase Microextraction and Related Techniques)

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19 pages, 3159 KiB

Open AccessArticle

Volatile Organic Compounds (VOCs) Produced by Levilactobacillus brevis WLP672 Fermentation in Defined Media Supplemented with Different Amino Acids

by Sarathadevi Rajendran, Patrick Silcock and Phil Bremer

Molecules 2024, 29(4), 753; https://doi.org/10.3390/molecules29040753 - 6 Feb 2024

Cited by 3 | Viewed by 1635

Abstract

Fermentation by lactic acid bacteria (LAB) is a promising approach to meet the increasing demand for meat or dairy plant-based analogues with realistic flavours. However, a detailed understanding of the impact of the substrate, fermentation conditions, and bacterial strains on the volatile organic compounds (VOCs) produced during fermentation is lacking. As a first step, the current study used a defined medium (DM) supplemented with the amino acids L-leucine (Leu), L-isoleucine (Ile), L-phenylalanine (Phe), L-threonine (Thr), L-methionine (Met), or L-glutamic acid (Glu) separately or combined to determine their impact on the VOCs produced by Levilactobacillus brevis WLP672 (LB672). VOCs were measured using headspace solid-phase microextraction (HS-SPME) gas chromatography–mass spectrometry (GC-MS). VOCs associated with the specific amino acids added included: benzaldehyde, phenylethyl alcohol, and benzyl alcohol with added Phe; methanethiol, methional, and dimethyl disulphide with added Met; 3-methyl butanol with added Leu; and 2-methyl butanol with added Ile. This research demonstrated that fermentation by LB672 of a DM supplemented with different amino acids separately or combined resulted in the formation of a range of dairy- and meat-related VOCs and provides information on how plant-based fermentations could be manipulated to generate desirable flavours. Full article

(This article belongs to the Special Issue Applications of Solid-Phase Microextraction and Related Techniques)

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15 pages, 1895 KiB

Open AccessArticle

An Automated Micro Solid-Phase Extraction (μSPE) Liquid Chromatography-Mass Spectrometry Method for Cyclophosphamide and Iphosphamide: Biological Monitoring in Antineoplastic Drug (AD) Occupational Exposure

by Stefano Dugheri, Donato Squillaci, Valentina Saccomando, Giorgio Marrubini, Elisabetta Bucaletti, Ilaria Rapi, Niccolò Fanfani, Giovanni Cappelli and Nicola Mucci

Molecules 2024, 29(3), 638; https://doi.org/10.3390/molecules29030638 - 30 Jan 2024

Viewed by 1212

Abstract

Despite the considerable steps taken in the last decade in the context of antineoplastic drug (AD) handling procedures, their mutagenic effect still poses a threat to healthcare personnel actively involved in compounding and administration units. Biological monitoring procedures usually require large volumes of sample and extraction solvents, or do not provide adequate sensitivity. It is here proposed a fast and automated method to evaluate the urinary levels of cyclophosphamide and iphosphamide, composed of a miniaturized solid phase extraction (µSPE) followed by ultrahigh-performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS) analysis. The extraction procedure, developed through design of experiments (DoE) on the ePrep One Workstation, required a total time of 9.5 min per sample, with recoveries of 77–79% and a solvent consumption lower than 1.5 mL per 1 mL of urine sample. Thanks to the UHPLC-MS/MS method, the limits of quantification (LOQ) obtained were lower than 10 pg/mL. The analytical procedure was successfully applied to 23 urine samples from compounding wards of four Italian hospitals, which resulted in contaminations between 27 and 182 pg/mL. Full article

(This article belongs to the Special Issue Applications of Solid-Phase Microextraction and Related Techniques)

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17 pages, 2508 KiB

Open AccessArticle

Magnetic Persimmon Leaf Composite: Preparation and Application in Magnetic Solid-Phase Extraction of Pesticides in Water Samples

by Yuyue Zang, Na Hang, Jiale Sui, Senlin Duan, Wanning Zhao, Jing Tao and Songqing Li

Molecules 2024, 29(1), 45; https://doi.org/10.3390/molecules29010045 - 20 Dec 2023

Viewed by 1077

Abstract

In recent years, the utilization of biomass materials for the removal and detection of water pollutants has garnered considerable attention. This study introduces, for the first time, the preparation of Fe₃O₄/persimmon leaf magnetic biomass composites. The magnetic composites were employed in a magnetic solid-phase extraction method, coupled with gas chromatography-electron capture detection (GC-ECD), for the analysis of four pesticides (trifluralin, triadimefon, permethrin, and fenvalerate) in environmental water samples. The innovative magnetic persimmon leaf composites were synthesized by in situ generation of Fe₃O₄ nanoparticles through coprecipitation and loaded onto persimmon leaves. These composites exhibit superparamagnetism with a saturation magnetization of 12.8 emu g⁻¹, facilitating rapid phase separation using a magnetic field and reducing the extraction time to 10 min. Desorption can be achieved within 30 s by aspirating 20 times, eliminating the need for time-consuming and labor-intensive experimental steps like filtration and centrifugation. The specific surface area of the magnetic composite adsorbent increased from 1.3279 m² g⁻¹ for the original persimmon leaf to 5.4688 m² g⁻¹. The abundant hydroxyl and carboxyl groups on the composites provide ample adsorption sites, resulting in adsorption capacities ranging from 55.056 mg g⁻¹ to 73.095 mg g⁻¹ for the studied pesticides. The composites exhibited extraction recoveries ranging from 80% to 90% for the studied pesticides. Compared to certain previously reported MSPE methods, this approach achieves equivalent or higher extraction recoveries in a shorter operation time, demonstrating enhanced efficiency and convenience. Good linearity of the target analytes was obtained within the range of 0.75–1500 μg L⁻¹, with a determination of coefficient (R²) greater than 0.999. These findings contribute to the use of magnetic persimmon leaf biomass materials as effective and environmentally friendly adsorbents for pollutant determination in water samples. Full article

(This article belongs to the Special Issue Applications of Solid-Phase Microextraction and Related Techniques)

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13 pages, 2134 KiB

Open AccessArticle

Preparation of COPs Mixed Matrix Membrane for Sensitive Determination of Six Sulfonamides in Human Urine

by Ying Liu, Yong Zhang, Jing Wang, Kexin Wang, Shuming Gao, Ruiqi Cui, Fubin Liu and Guihua Gao

Molecules 2023, 28(21), 7336; https://doi.org/10.3390/molecules28217336 - 30 Oct 2023

Cited by 1 | Viewed by 1245

Abstract

In this study, TpDMB-COPs, a specific class of covalent organic polymers (COPs), was synthesized using Schiff-base chemistry and incorporated into a polyvinylidene fluoride (PVDF) polymer for the first time to prepare COPs mixed matrix membranes (TpDMB-COPs-MMM). A membrane solid-phase extraction (ME) method based on the TpDMB-COPs-MMM was developed to extract trace levels of six sulfonamides from human urine identified by high-performance liquid chromatography (HPLC). The key factors affecting the extraction efficiency were investigated. Under the optimum conditions, the proposed method demonstrated an excellent linear relationship in the range of 3.5–25 ng/mL (r² ≥ 0.9991), with the low limits of detection (LOD) between 1.25 ng/mL and 2.50 ng/mL and the limit of quantification (LOQ) between 3.50 ng/mL and 7.00 ng/mL. Intra-day and inter-day accuracies were below 5.0%. The method’s accuracy was assessed by recovery experiments using human urine spiked at three levels (7–14 ng/mL, 10–15 ng/mL, and 16–20 ng/mL). The recoveries ranged from 87.4 to 112.2% with relative standard deviations (RSD) ≤ 8.7%, confirming the applicability of the proposed method. The developed ME method based on TpDMB-COPs-MMM offered advantages, including simple operation, superior extraction affinity, excellent recycling performance, and easy removal and separation from the solution. The prepared TpDMB-COPs-MMM was demonstrated to be a promising adsorbent for ME in the pre-concentration of trace organic compounds from complex matrices, expanding the application of COPs and providing references for other porous materials in sample pre-treatment. Full article

(This article belongs to the Special Issue Applications of Solid-Phase Microextraction and Related Techniques)

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16 pages, 1293 KiB

Open AccessArticle

A New Perspective on SPME and SPME Arrow: Formaldehyde Determination by On-Sample Derivatization Coupled with Multiple and Cooling-Assisted Extractions

by Stefano Dugheri, Giovanni Cappelli, Niccolò Fanfani, Jacopo Ceccarelli, Giorgio Marrubini, Donato Squillaci, Veronica Traversini, Riccardo Gori, Nicola Mucci and Giulio Arcangeli

Molecules 2023, 28(14), 5441; https://doi.org/10.3390/molecules28145441 - 16 Jul 2023

Cited by 4 | Viewed by 1764

Abstract

Formaldehyde (FA) is a toxic compound and a human carcinogen. Regulating FA-releasing substances in commercial goods is a growing and interesting topic: worldwide production sectors, like food industries, textiles, wood manufacture, and cosmetics, are involved. Thus, there is a need for sensitive, economical, and specific FA monitoring tools. Solid-phase microextraction (SPME), with O-(2,3,4,5,6-pentafluorobenzyl)-hydroxylamine (PFBHA) on-sample derivatization and gas chromatography, is proposed for FA monitoring of real-life samples. This study reports the use of polydimethylsiloxane (PDMS) as a sorbent phase combined with innovative commercial methods, such as multiple SPME (MSPME) and cooling-assisted SPME, for FA determination. Critical steps, such as extraction and sampling, were evaluated in method development. The derivatization was performed at 60 °C for 30 min, followed by 15 min sampling at 10 °C, in three cycles (SPME Arrow) or six cycles (SPME). The sensitivity was satisfactory for the method’s purposes (LOD-LOQ at 11-36 ng L⁻¹, and 8-26 ng L⁻¹, for SPME and SPME Arrow, respectively). The method’s linearity ranges from the lower LOQ at trace level (ng L⁻¹) to the upper LOQ at 40 mg L⁻¹. The precision range was 5.7–10.2% and 4.8–9.6% and the accuracy was 97.4% and 96.3% for SPME and SPME Arrow, respectively. The cooling MSPME set-up applied to real commercial goods provided results of quality comparable to previously published data. Full article

(This article belongs to the Special Issue Applications of Solid-Phase Microextraction and Related Techniques)

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13 pages, 1650 KiB

Open AccessArticle

Synthesis and Characterization of a Multi-Walled Carbon Nanotube–Ionic Liquid/Polyaniline Adsorbent for a Solvent-Free In-Needle Microextraction Method

by Soyoung Ahn and Sunyoung Bae

Molecules 2023, 28(8), 3517; https://doi.org/10.3390/molecules28083517 - 17 Apr 2023

Cited by 4 | Viewed by 1582

Abstract

Sample preparation is an essential process when handling complex matrices. Extraction without using a solvent requires the direct transfer of analytes from the sample to the adsorbent either in the gas or liquid phase. In this study, a wire coated with a new adsorbent was fabricated for in-needle microextraction (INME) as a solvent-free sample extraction method. The wire inserted into the needle was placed in the headspace (HS), which was saturated with volatile organic compounds from the sample in a vial. A new adsorbent was synthesized via electrochemical polymerization by mixing aniline with multi-walled carbon nanotubes (MWCNTs) in the presence of an ionic liquid (IL). The newly synthesized adsorbent using IL is expected to achieve high thermal stability, good solvation properties, and high extraction efficiency. The characteristics of the electrochemically synthesized surfaces coated with MWCNT–IL/polyaniline (PANI) adsorbents were characterized using Fourier transform infrared (FTIR) spectroscopy, scanning electron microscopy (SEM), thermogravimetric analysis (TGA), and atomic force microscopy (AFM). Then, the proposed HS–INME–MWCNT–IL/PANI method was optimized and validated. Accuracy and precision were evaluated by analyzing replicates of a real sample containing phthalates, showing spike recovery between 61.13% and 108.21% and relative standard deviations lower than 15%. The limit of detection and limit of quantification of the proposed method were computed using the IUPAC definition as 15.84~50.56 μg and 52.79~168.5 μg, respectively. We concluded that HS–INME using a wire coated with the MWCNT–IL/PANI adsorbent could be repeatedly used up to 150 times without degrading its extraction performance in an aqueous solution; it constitutes an eco-friendly and cost-effective extraction method. Full article

(This article belongs to the Special Issue Applications of Solid-Phase Microextraction and Related Techniques)

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15 pages, 2445 KiB

Open AccessArticle

The Difference of Volatile Compounds in Female and Male Buds of Trichosanthes anguina L. Based on HS-SPME-GC-MS and Multivariate Statistical Analysis

by Pingping Song, Bo Xu, Zhenying Liu, Yunxia Cheng and Zhimao Chao

Molecules 2022, 27(20), 7021; https://doi.org/10.3390/molecules27207021 - 18 Oct 2022

Cited by 6 | Viewed by 1671

Abstract

Trichosanthes anguina L. (family Cucurbitaceae) is a monoecious and diclinous plant that can be consumed as a vegetable and has anti-inflammatory and antioxidant effects. The chemical composition and content of volatile compounds in female and male buds of T. anguina were explored by headspace solid-phase microextraction-gas chromatography-mass spectrometry (HS-SPME-GC-MS) technology combined with multivariate statistical analysis. The results showed that the content of the volatile compounds was different between female and male buds. 2,2,6-trimethyl-6-vinyltetrahydro-2H-pyran-3-ol and 2,2,6-trimethyl-6-vinyldihydro-2H-pyran-3(4H)-one were the main volatile compounds in both female and male buds. Based on the multivariate statistical analysis of orthogonal projections to latent structures discriminant analysis (OPLS-DA) and t-test, the content of seven compounds was significantly different between female and male buds. The content of three compounds in male buds was higher than that in female, i.e., (E)-4,8-dimethyl-1,3,7-nonatriene, 1,5,9,9-tetramethyl-1,4,7-cycloundecatriene, and (E)-caryophyllene. Conversely, the content of (Z)-4-hexen-1-ol, (Z)-3-hexenyl benzoate, (Z)-3-hexenyl salicylate, and 2-hexen-1-ol in female buds was higher than that in male buds. This is the first report on the difference in the volatile compounds between female and male buds of T. anguina, which enriches the basic research on the monoecious and diclinous plant and provides a reference for the study of plant sex differentiation. Full article

(This article belongs to the Special Issue Applications of Solid-Phase Microextraction and Related Techniques)

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21 pages, 4395 KiB

Open AccessFeature PaperReview

Developments and Applications of Molecularly Imprinted Polymer-Based In-Tube Solid Phase Microextraction Technique for Efficient Sample Preparation

by Hiroyuki Kataoka, Atsushi Ishizaki, Keita Saito and Kentaro Ehara

Molecules 2024, 29(18), 4472; https://doi.org/10.3390/molecules29184472 - 20 Sep 2024

Cited by 1 | Viewed by 1594

Abstract

Despite advancements in the sensitivity and performance of analytical instruments, sample preparation remains a bottleneck in the analytical process. Currently, solid-phase extraction is more widely used than traditional organic solvent extraction due to its ease of use and lower solvent requirements. Moreover, various microextraction techniques such as micro solid-phase extraction, dispersive micro solid-phase extraction, solid-phase microextraction, stir bar sorptive extraction, liquid-phase microextraction, and magnetic bead extraction have been developed to minimize sample size, reduce solvent usage, and enable automation. Among these, in-tube solid-phase microextraction (IT-SPME) using capillaries as extraction devices has gained attention as an advanced “green extraction technique” that combines miniaturization, on-line automation, and reduced solvent consumption. Capillary tubes in IT-SPME are categorized into configurations: inner-wall-coated, particle-packed, fiber-packed, and rod monolith, operating either in a draw/eject system or a flow-through system. Additionally, the developments of novel adsorbents such as monoliths, ionic liquids, restricted-access materials, molecularly imprinted polymers (MIPs), graphene, carbon nanotubes, inorganic nanoparticles, and organometallic frameworks have improved extraction efficiency and selectivity. MIPs, in particular, are stable, custom-made polymers with molecular recognition capabilities formed during synthesis, making them exceptional “smart adsorbents” for selective sample preparation. The MIP fabrication process involves three main stages: pre-arrangement for recognition capability, polymerization, and template removal. After forming the template-monomer complex, polymerization creates a polymer network where the template molecules are anchored, and the final step involves removing the template to produce an MIP with cavities complementary to the template molecules. This review is the first paper to focus on advanced MIP-based IT-SPME, which integrates the selectivity of MIPs into efficient IT-SPME, and summarizes its recent developments and applications. Full article

(This article belongs to the Special Issue Applications of Solid-Phase Microextraction and Related Techniques)

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28 pages, 2534 KiB

Open AccessReview

Advances and Applications of Hybrid Graphene-Based Materials as Sorbents for Solid Phase Microextraction Techniques

by Alessandra Timóteo Cardoso, Rafael Oliveira Martins and Fernando Mauro Lanças

Molecules 2024, 29(15), 3661; https://doi.org/10.3390/molecules29153661 - 2 Aug 2024

Viewed by 1194

Abstract

The advancement of traditional sample preparation techniques has brought about miniaturization systems designed to scale down conventional methods and advocate for environmentally friendly analytical approaches. Although often referred to as green analytical strategies, the effectiveness of these methods is intricately linked to the properties of the sorbent utilized. Moreover, to fully embrace implementing these methods, it is crucial to innovate and develop new sorbent or solid phases that enhance the adaptability of miniaturized techniques across various matrices and analytes. Graphene-based materials exhibit remarkable versatility and modification potential, making them ideal sorbents for miniaturized strategies due to their high surface area and functional groups. Their notable adsorption capability and alignment with green synthesis approaches, such as bio-based graphene materials, enable the use of less sorbent and the creation of biodegradable materials, enhancing their eco-friendly aspects towards green analytical practices. Therefore, this study provides an overview of different types of hybrid graphene-based materials as well as their applications in crucial miniaturized techniques, focusing on offline methodologies such as stir bar sorptive extraction (SBSE), microextraction by packed sorbent (MEPS), pipette-tip solid-phase extraction (PT-SPE), disposable pipette extraction (DPX), dispersive micro-solid-phase extraction (d-µ-SPE), and magnetic solid-phase extraction (MSPE). Full article

(This article belongs to the Special Issue Applications of Solid-Phase Microextraction and Related Techniques)

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48 pages, 5365 KiB

Open AccessReview

Supramolecular Materials as Solid-Phase Microextraction Coatings in Environmental Analysis

by Nicolò Riboni, Erika Ribezzi, Federica Bianchi and Maria Careri

Molecules 2024, 29(12), 2802; https://doi.org/10.3390/molecules29122802 - 12 Jun 2024

Cited by 2 | Viewed by 1329

Abstract

Solid-phase microextraction (SPME) has been widely proposed for the extraction, clean-up, and preconcentration of analytes of environmental concern. Enrichment capabilities, preconcentration efficiency, sample throughput, and selectivity in extracting target compounds greatly depend on the materials used as SPME coatings. Supramolecular materials have emerged as promising porous coatings to be used for the extraction of target compounds due to their unique selectivity, three-dimensional framework, flexible design, and possibility to promote the interaction between the analytes and the coating by means of multiple oriented functional groups. The present review will cover the state of the art of the last 5 years related to SPME coatings based on metal organic frameworks (MOFs), covalent organic frameworks (COFs), and supramolecular macrocycles used for environmental applications. Full article

(This article belongs to the Special Issue Applications of Solid-Phase Microextraction and Related Techniques)

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